[markivvv]

Hi guys, I'm trying to interpret some logs I took. I've read the "how to log" megapost, which is amazing, but would appreciate inputs from you guys as well.

I have a:
2011 PWG F10 RWD (sorry I know it's the F30 forum)
MHD Stage 1 91oct tune with 93oct in the tank
MST Relocated intake
Stock DP/IC/CP
New Bosch OEM plugs (stock gap, 0.031) and Delphi coils installed 1k miles ago
New Mahle VC installed 1k miles ago
FTP chargepipe waiting to be installed when the weather gets better
No active/shadow codes, no CEL, no misfires, no cold start issues, no rough idle

I've been experiencing an intermittent hesitation/jerk when I get on the throttle. I recorded these two logs yesterday. Sport+ 4th gear 2500-6000rpm

Log 1 - https://datazap.me/u/markivvv/cyl5-t...37-38-39-40-41

Log 2 - https://datazap.me/u/markivvv/0209-6...37-38-39-40-41

Noticing a few things here. Overboosting by about 1psi which I'm hearing is normal for PWG. In Log 1, I got a nasty timing correction on Cyl 5, pulling -7.2 degrees of timing, but this was not the case in log 2. Getting a similar throttle curve with closures on both logs - starts off at 100%, ramps down to 59%, ramps up to 90ish again, then comes back down. Also noticing low STFTs (-15 to -20) in both logs. Knock interpolation is 0 in both logs.

Did a spirited drive today with the Live Data gauges open, did multiple WOT pulls (logs were no good though) and noticed that all cylinders were pulling timing, ranging from -1 to -5 degrees, most of them around -3.

What could potentially cause these? I got gas from a different gas station this time around (I usually do Shell 93) so I'm not ruling out bad gas. This could explain the timing corrections but doesn't explain the throttle closures or STFT.

The relocated intake was installed by the previous owner so it's been on the car for 4-5 years by this point with no issues, but the car was not tuned under his ownership, or mine until recently. Didn't notice any issues with it when I was on stock map. Could that cause the throttle curve / STFT dip?

Cylinder 5 had one really bad timing correction but it doesn't seem to be consistent, nor am I experiencing any cold start issues / rough idles / misfires. Would I be able to rule out injector issues?

Would appreciate any advice thank you so much

[thejeremyman9]

The large correction on a single cylinder could be a fluke. If its recurring, could be something up with that cyl.

Misc corrections across all cyl is usually fuel. But also pretty normal. Most of the time you will have ~-3 degree cross misc cylinders unless you are running higher octane fuel than tune (i.e., 93 oct on 91 tune).

The STFTs could be because of the intake or a leak.

[markivvv]

Originally Posted by thejeremyman9

The large correction on a single cylinder could be a fluke. If its recurring, could be something up with that cyl.

Misc corrections across all cyl is usually fuel. But also pretty normal. Most of the time you will have ~-3 degree cross misc cylinders unless you are running higher octane fuel than tune (i.e., 93 oct on 91 tune).

The STFTs could be because of the intake or a leak.

Got it, appreciate the reply. Your "how to log" thread was probably the most helpful thread I've read on here, thanks for taking the time to post it. I'm very new to owning/working on/understanding these cars, but your thread explained everything in a very intuitive and easy to understand way, so I just wanted to say I appreciate it.

As far as the car goes tho, it's actually gotten worse since my last post. It's been consistently overboosting by 1-2 psi for a while now, causing some pretty big throttle closures but it's gotten much worse recently.

Last week, the vacuum line going into the boost solenoid from the valve cover ended up ripping, and I lost all boost. I replaced it with a line of similar length/inner diameter from my local auto parts store and was able to make boost again. For the last couple days, the overboost has been much more severe. I'm consistently boosting 2psi over target, causing the throttle to close even more. In one instance, I ended up hitting 18psi, which caused the car to go into limp mode and threw 120208/120408 (charge pressure too high / switched off as consequence). I actually was logging during this time so I caught it.

https://datazap.me/u/markivvv/0221-n...og=0&data=4-18 - that link has two log charts. During the first log, boost hit 18psi so I let off. Took the second log a couple min later, car went into limp mode at the end of that.

I tried a couple different scenarios. Slowly rolling into the throttle across multiple gears (without going WOT) also seems to result in a similar overboost scenario, but I have no idea how to even begin interpreting this log. WGDC is fluctuating like crazy, boost is way over target, throttle is closing down to 29% - https://datazap.me/u/markivvv/rollin...1&data=4-19-31

I have a new boost solenoid on order from FCP. I kinda assumed it was the issue, but it might be worth replacing it either way. After thinking about it a little more, Is there a chance that there's something wrong with the vacuum line I replaced, maybe it's not strong enough etc? I made sure to get one with the same inner diameter, but is there anything else I should've taken into account?